Patent Application
20130230418
This application is based on Japanese Patent Application No. 2012-46101 filed on Mar. 2, 2012, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to a fuel supply apparatus.
JP-2005-155602A (US 2005/0100461) describes a fuel supply apparatus which supplies fuel discharged from a fuel pump to a cooling passage defined in a flange so as to cool a control circuit disposed on the flange.
In JP-2005-155602A, a tube is provided between the fuel pump and the flange so as to supply fuel to the cooling passage. Further, a connector is provided between the fuel pump and the flange to connect the fuel pump and the flange with each other. That is, both of the connector and the tube are provided between the flange and the fuel pump, so the structure of the fuel supply apparatus becomes complicated.
According to an example of the present disclosure, a fuel supply apparatus supplying fuel from a fuel tank to a fuel-consuming device includes an electric pump, a control circuit, a lid component, and a connection component. The electric pump is disposed in the fuel tank, and includes a pressure raising part which raises a pressure of the fuel in the fuel tank, and a fuel outlet part which flows out the fuel having the pressure raised by the pressure raising part. The control circuit controls electric power supplied to the electric pump. The lid component covers an opening of the fuel tank, and has a circulation part and an installation part. The circulation part defines a circulation space in which the fuel flowing from the fuel outlet part circulates. The installation part has a first surface facing the circulation space, and a second surface to which the control circuit is arranged. The connection component is formed into a cylindrical shape to connect the lid component and the electric pump with each other, and defines a communicating path inside. The fuel outlet part and the circulation space communicate with each other through the communicating path.
The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:
Embodiments of the present disclosure will be described hereafter referring to drawings. In the embodiments, a part that corresponds to a matter described in a preceding embodiment may be assigned with the same reference numeral, and redundant explanation for the part may be omitted. When only a part of a configuration is described in an embodiment, another preceding embodiment may be applied to the other parts of the configuration. The parts may be combined even if it is not explicitly described that the parts can be combined. The embodiments may be partially combined even if it is not explicitly described that the embodiments can be combined, provided there is no harm in the combination.
The fuel supply apparatus 100 has a flange 10, a subtank 20, a covering 30, an adjustment mechanism 40, a pump unit 50, a residual quantity detecting element 70, and a controller 80. The subtank 20, the covering 30, the adjustment mechanism 40, the pump unit 50, and the residual quantity detecting element 70 are arranged at specified positions, respectively, in the fuel tank 200.
The flange 10 is made of resin, and has a disc shape, as shown in
As shown in
The subtank 20 is made of resin, and has a based cylinder shape. The subtank 20 is accommodated in the fuel tank 200, and is located on a bottom 200c of the fuel tank 200. A jet pump 21 is arranged on a bottom 20a of the subtank 20. The jet pump 21 has an introductory passage 22 and a jet nozzle 23. The introductory passage 22 causes the inside of the fuel tank 200 and the inside of the subtank 20 to communicate with each other. The jet nozzle 23 injects fuel discharged from a pressure regulator 68 of the pump unit 50 toward the introductory passage 22. When the fuel is injected, a negative pressure lower than an atmospheric pressure occurs in the introductory passage 22. Therefore, fuel in the fuel tank 200 is transported into the subtank 20 through the introductory passage 22. The subtank 20 stores the fuel.
The covering 30 is made of resin, and has a based cylinder shape. The covering 30 is arranged in a manner that a base part of the covering 30 is located on the upper side. An opening edge of the covering 30 is fitted with an opening edge of the subtank 20. Thereby, the opening of the subtank 20 is closed by the covering 30. The covering 30 has a first holding part 31, a second holding part 32 and an accommodation part 33. The first holding part 31 holds the pump unit 50 in the fuel tank 200, and the second holding part 32 holds the residual quantity detecting element 70 in the fuel tank 200. The accommodation part 33 has a based cylinder shape and accommodates the pillar 41.
As shown in
The intermediate part 42 is made of resin, and has a double tube shape. The intermediate part 42 is coaxially accommodated by the accommodation part 33 in a state where the pillar 41 is inserted between an inner tube 43 and an outer tube 44 of the intermediate part 42. An engaging nail 43a is projected from the inner tube 43, and engages with the pillar 41, thereby fixing the intermediate part 42 to a lower end part 41b of the pillar 41.
Moreover, the intermediate part 42 is slidingly fitting to a double thread 33a extended in the axial direction on the inner circumference face of the accommodation part 33. Thus, the intermediate part 42 is regulated from having relative rotation in the circumference direction and is allowed to have axial movement relative to the accommodation part 33. The subtank 20, the covering 30, the pump unit 50, and the residual quantity detecting element 70 are integrated with each other and are movable in the axial direction relative to the pillar 41 and not rotatable in the circumference direction of the pillar 41.
The pillar 41 is fixed to the fix portion 11 when an engaging nail 11g projected from the fix portion 11 is engaged with an upper end 41a of the pillar 41. Thus, a unit is constructed by integrating the flange 10, the subtank 20, the covering 30, the pump unit 50, and the residual quantity detecting element 70 which are connected with each other through the pillar 41.
A lower part of the pump unit 50 is accommodated in the subtank 20, and an upper part of the pump unit 50 is projected from the covering 30. As shown in
The electric pump 54 is located on the upper side of the suction filter 51, and has an inlet port 54a, a discharge port 54b and a vapor exhaust port 54c. The inlet port 54a and the vapor exhaust port 54c face downward, and the discharge port 54b faces upward. As shown in
The pressure raising part 55 has a rotation member 56 and a pump chamber 57. The rotation member 56 is driven by an electric motor 58 and is accommodated in the pump chamber 57 which communicates with the inlet port 54a, the discharge port 54b and the vapor exhaust port 54c. The rotation member 56 is a disc-shaped impeller having plural blade grooves arranged in the circumference direction, and is located inside the pump chamber 57 in a state where the axis direction substantially corresponds with the up-and-down direction.
The electric motor 58 is electrically connected with the control circuit 81 of the controller 80 through a flexible wiring 60 which can be bent flexibly. The electric motor 58 rotates the rotation member 56 using electric power supplied from the control circuit 81. When the rotation member 56 is rotated, fuel is drawn from the inlet port 54a through the suction filter 51 into the subtank 20. Further, the pressure of fuel is raised the blade groove of the rotation member 56 in the pump chamber 57, and the pressure-raised fuel is discharged from the discharge port 54b.
Moreover, vapor (air) occurs in the fuel drawn from the inlet port 54a, because of the rotation of the rotation member 56. The air, which affects the pressure raising, is discharged with the fuel from the vapor exhaust port 54c communicating with the pump chamber 57.
The suction filter 51 is located on the most bottom part of the pump unit 50. The suction filter 51 is connected with the inlet port 54a of the electric pump 54, and removes a relatively large foreign matter from fuel to be drawn by the electric pump 54 from the subtank 20.
The suction filter 51 has a core component 52 and a filter-medium sheet 53. The core component 52 is made of resin, and has a based cylinder shape. The filter-medium sheet 53 covers the outer side of the core component 52. A portion of the electric pump 54 having the inlet port 54a, the vapor exhaust port 54c and the pump chamber 57 is coaxially accommodated on the inner circumference side of the peripheral wall of the core component 52. In this state, an upper end of the peripheral wall of the core component 52 is mounted to a filter case 62 of the fuel filter 61.
Moreover, a fuel passage connected to the inlet port 54a penetrates the bottom wall part of the core component 52. Furthermore, a discharge passage 52a also penetrates a center section of the bottom wall part around the fuel passage. Due to the discharge passage 52a, fuel located between the lower end part of the electric pump 54 and the bottom wall part of the core component 52 flows downward. Thereby, the fuel in the pressure raising state, which contains air, is discharged from the vapor exhaust port 54c between the lower end part of the electric pump 54 and the bottom wall part of the core component 52, and then is discharged from the discharge passage 52a.
The filter-medium sheet 53 may be constructed by, for example, fibrous nonwoven cloth having single layer or multi layers, mesh cloth, or filter paper. Alternatively, the filter-medium sheet 53 may be constructed by layering at least two kinds of the nonwoven cloth, the mesh cloth, and the filter paper. The filter-medium sheet 53 is arranged to cover the outer side of the core component 52. Moreover, a clearance is generated between the core component 52 and the peripheral wall part and the bottom wall part of the filter-medium sheet 53 in the state where the filter-medium sheet 53 covers the outer side of the core component 52. Furthermore, the filter-medium sheet 53 has a hole defining the discharge passage 52a. The filter-medium sheet 53 is fixed to the core component 52 made of resin by welding or bonding.
Fuel drawn from the inside of the subtank 20 toward the inlet port 54a of the electric pump 54 is filtered by the filter-medium sheet 53 of the suction filter 51, and is led to the inlet port 54a through the fuel passage of the core component 52. Furthermore, fuel discharged from the vapor exhaust port 54c is discharged outside from the discharge passage 52a after staying between the bottom wall part and the electric pump 54 in the core component 52.
The fuel filter 61 is arranged to cover the electric pump 54 from the outer circumference side and the upper side. The filter case 62 of the fuel filter 61 is made of resin, and has a double tube constructed by an inner pipe 63 and an outer pipe 64. The electric pump 54 is coaxially arranged on the inner circumference side of the inner pipe 63. A filter element 65 of the fuel filter 61 is made of, for example, a honeycomb-shaped filter medium which is accommodated between the inner pipe 63 and the outer pipe 64.
A space between the inner pipe 63 and the outer pipe 64 communicates with the discharge port 54b of the electric pump 54 on the upstream side of the filter element 65 in the fuel flow, and communicates with a fuel outlet 66 of the fuel filter 61 on the downstream side of the filter element 65 in the fuel flow. The fuel outlet 66 is connected with the fuel delivery tube 14 through a flexible tube 67 which can be bent flexibly. Thus, fuel discharged from the discharge port 54b is supplied to the fuel delivery tube 14 from the fuel outlet 66 with a state where minute foreign matters has been removed by the filter element 65.
As shown in
As shown in
The controller 80 is arranged outside of the fuel tank 200 and is provided to the flange 10. The controller 80 has the control circuit 81 and a covering 82. The control circuit 81 controls the electric power supply to the electric pump 54. The control circuit 81 is disposed on the installation part 13 of the flange 10. The covering 82 is provided to the flange 10 to cover the control circuit 81.
The covering 82 is made of resin, and, as shown in
Details of the flange 10, the adjustment mechanism 40, and the pump unit 50 will be explained.
The flange 10 has the installation part 13 and the fix portion 11. The installation part 13 is made of polyacetal (POM) as a base material, which contains glass fiber, ferrite powder, etc. having a heat conductivity higher than that of the POM. The installation part 13 has the rectangle shape, as shown in
On the other hand, as shown in
The fix portion 11 is made of POM and has a concave portion 11a and a pipe part 11f. The concave portion 11a is formed under the installation part 13. The concave portion 11a has a pipe wall 11b and a bottom wall 11c. The pipe wall 11b is projected in a cylindrical shape downward from the peripheral edge part of the fin 13c. The bottom wall 11c covers the lower end part of the pipe wall 11b.
The concave portion 11a has an opening part 11d, and the installation part 13 is arranged to cover the opening part 11d. The opening part 11d and the installation part 13 are joined with each other by welding. Due to the installation part 13 and the fix portion 11, the circulation space 12 is defined inside the concave portion 11a, that is, the circulation space 12 is defined on the inner circumference space of the pipe wall 11b.
The pipe part 11f extends downward from the bottom wall 11c. The inside space of the concave portion 11a communicates with an outside space of the fix portion 11 through the pipe part 11f. The upper end 41a of the pillar 41 is press-fitted into the pipe part 11f. The pipe part 11f has the engaging nail 11g which engages with the pillar 41, when the upper end 41a is press-fitted. Moreover, the bottom wall 11c has a communication hole 11e through which the circulation space 12 and the inside space of the fuel tank 200 communicate with each other, and the communication hole 11e is located adjacent to the pipe part 11f.
The adjustment mechanism 40 will be described in details. The pillar 41 has a communicating path 41c inside to introduce fuel to the circulation space 12 of the fix portion 11. The pillar 41 is provided coaxially with the pipe part 11f of the fix portion 11. The inner tube 43, which is placed on the inner circumference side of the pillar 41, has a bottom part 43b. The bottom part 43b has a cylindrical support part 43c extending from the bottom part 43b toward the bottom 33b of the accommodation part 33.
The support part 43c supports the upper end of the elastic component 45. The bottom 33b of the accommodation part 33 has a cylindrical support part 33c extending toward the bottom part 43b of the inner tube 43. The support part 33c supports the lower end part of the elastic component 45. Due to the inner tube 43 and the accommodation part 33, a predetermined space is defined between the bottom part 43b of the inner tube 43 and the bottom 33b of the accommodation part 33. The predetermined space communicates with the inside of the pillar 41 through the support part 43c, and communicates with the subtank 20 through the support part 33c. That is, the communicating path 41c communicates with the inside of the subtank 20 through the space between the bottom part 43b and the bottom 33b.
The pump unit 50 will be described in details. As shown in
When a person inputs a signal to start the combustion engine 300, a control device of the combustion engine 300 outputs a control signal to start the fuel supply apparatus 100. When the control signal is input into the controller 80, the control circuit 81 supplies electric power to the electric pump 54 based on the inputted control signal, thereby driving the electric pump 54 to rotate the rotation member 56. Fuel is drawn from the inlet port 54a, and the pressure of the fuel in the pump chamber 57 is raised. The fuel filter 61 removes a foreign matter from the fuel discharged from the discharge port 54b after the pressure is raised in the pump chamber 57, and the pressure of the fuel is controlled by the pressure regulator 68. Then, the fuel is supplied to the combustion engine 300 from the fuel delivery tube 14.
The fuel supplied to the combustion engine 300 from the fuel delivery tube 14 is changed depending on the operational status of the combustion engine 300. For example, when the combustion engine 300 is in idol operational status, the fuel consumption amount of the combustion engine 300 is smaller than that in a state where the vehicle is accelerated. Therefore, most of the fuel supplied from the electric pump 54 is discharged into the subtank 20 rather than the pressure regulator 68. At this time, the fuel whose pressure is in the raising state and containing air is also discharged from the vapor exhaust port 54c. A certain amount of the fuel is discharged from the vapor exhaust port 54c, not depending on the fuel consumption amount of the combustion engine 300.
The fuel discharged from the vapor exhaust port 54c flows into the flexible tube 69 through the discharge passage 52a. The fuel flows into the space between the accommodation part 33 and the intermediate part 42, and reaches the communicating path 41 c of the pillar 41. Furthermore, the fuel which reached the communicating path 41c flows into the circulation space 12 through the pipe part 11f of the fix portion 11. The fuel containing air and flowing into the circulation space 12 is discharged from the communication hole 11e. Thereby, a flow of the fuel is generated in the circulation space 12.
When the fuel flowing into the circulation space 12 contacts the fin 13c of the installation part 13, heat generated in the control circuit 81 will be absorbed by the fuel, so the control circuit 81 will be cooled. Then, the fuel is discharged from the communication hole 11e with air.
According to the first embodiment, the fuel pumped from the electric pump 54 is introduced into the circulation space 12 defined in the flange 10 through the communicating path 41c partitioned by the pillar 41. Therefore, a passage portion such as tube, which introduces fuel from the electric pump 54 to the circulation space 12, can be eliminated. Thus, the control circuit 81 which is disposed on the flange 10 can be cooled with the simple and easy structure.
Because the communication hole 11e is defined in the fix portion 11, the flow of fuel can be generated in the circulation space 12, thus, the fuel flowing into the circulation space 12 can be restricted from staying in the circulation space 12. Thus, the control circuit 81 can be securely cooled.
Moreover, the second surface 13b of the installation part 13 facing the circulation space 12 has the fin 13c. Therefore, the surface area of the second surface 13b can be increased. As a result, the cooling property can be raised.
Furthermore, the heat mover whose heat conductivity is higher than that of the base material (POM) of the installation part 13 is mixed in the POM, so the heat exchanging performance can be increased. As a result, the cooling efficiency can be raised. Moreover, the same resin (POM) is used for the base material of the installation part 13 and the fix portion 11. Therefore, the connection strength between the installation part 13 and the fix portion 11 can be raised to define the circulation space 12. Therefore, the sealing property of the circulation space 12 can be raised.
Furthermore, the vapor fuel (fuel containing air) is introduced from the vapor exhaust port 54c to the circulation space 12 while the pressure of fuel is being raised, at this time, a predetermined discharge amount of fuel is secured irrespective of the fuel consumption amount of the combustion engine 300. Therefore, the cooling effect is securable irrespective of the fuel consumption amount of the combustion engine 300.
The vapor exhaust port 54c discharges a part of the fuel whose pressure is being raised such that air is contained in the fuel. Generally, a common electric pump secures the increase in the pressure of the fuel by discharging the fuel containing air. Whenever the electric pump is driven, the fuel containing air is generated regardless of the fuel consumption amount of the engine 300.
Moreover, the fuel flowing out of the circulation space 12 through the communication hole 11e contacts the external wall surfaces 41d of the pillar 41, and then flows downward along the external wall surface 41d. Thus, the fuel which flowed into the circulation space 12 is discharged from the communication hole 11e. Therefore, the fuel in the fuel tank 200 can be restricted from being foamed, compared with a case where the fuel directly falls into the fuel in the fuel tank 200.
The communication hole 11e has the hole size in a manner that the amount of fuel discharged from the communication hole 11e becomes larger than or equal to the amount of the vapor fuel discharged from the vapor exhaust port 54c. Therefore, fuel can be appropriately discharged from the vapor exhaust port 54c with reliability. Thus, air which affects the pressure raising in the pump chamber 57 can be suitably discharged from the electric pump 54, so the pressure-raising property of the electric pump 54 can be secured.
The flange 10 may correspond to a lid component, and the fix portion 11 may correspond to a circulation part. The pillar 41 may correspond to a connection component. The vapor exhaust port 54c may correspond to a fuel outlet part and a vapor fuel discharge part.
In the first embodiment, the control circuit 81 is cooled by introducing the fuel discharged from the vapor exhaust port 54c to the circulation space 12. In contrast, in a second embodiment, a fuel supply apparatus 100a cools the control circuit 81 by introducing fuel from the fuel outlet 66 to the circulation space 12.
The second embodiment will be described with reference to
According to the second embodiment, the fuel flowing from the discharge port 54b of the electric pump 54 flows into the communicating path 41c of the pillar 41 through the fuel outlet 66 and the flexible tube 67a. The fuel flows into the circulation space 12 of the flange 10, and cools the control circuit 81. Then, the fuel is supplied to the combustion engine 300 through the fuel passage 16 and the fuel delivery tube 14. Therefore, a passage portion such as tube, which introduces fuel out of the fuel tank 200 from the electric pump 54, can be eliminated, so as to supply the fuel to the combustion engine 300. Thus, the structure of the fuel supply apparatus 100a can be simplified.
In the second embodiment, similarly to the first embodiment, the fin 13c may be formed in the installation part 13, and the heat mover with high heat conductivity may be mixed in the base material (POM) of the installation part 13.
Furthermore, the fix portion 11 and the installation part 13 may be welded with each other by using the same resin material as base material, so as to raise the connection strength. In the second embodiment, fuel is introduced into the circulation space 12 from the fuel outlet 66 where the fuel pressure is higher than that of the vapor fuel of the first embodiment. However, in this case, the sealing property of the circulation space 12 is securable by raising the connection strength.
In the second embodiment, the discharge port 54b may correspond to a fuel outlet part and a fuel discharge part.
Such changes and modifications are to be understood as being within the scope of the present disclosure as defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-46101 | Mar 2012 | JP | national |
